Make sure you've installed node.js and Grunt

Run npm install in this directory (the source root). This should install the required node.js modules. You might want to npm install -g coffee-script http-server also.

Clone my fork of Emscripten and checkout the pcejs branch. Add it to your $PATH so you can run emcc. Similarly you should be working with my fork of PCE on the pcejs branch, but that's where you're reading this, right?

Most of the build process involves running Grunt tasks. Run grunt --help for a list of possiblities.

Make sure you've got a directory containing a working set of files for the emulator. This means: a rom file, a config file, and some media (hard disk and/or floppy images). You can use a normal build of PCE test these out eg. one obtained from the website, or your package manager of choice (in my case, homebrew).

Your config file should be named pce-config.cfg. Once you've got these together in a directory, run grunt romdir:[your directory] which will symlink the directory into the source tree at roms/. This is necessary for when the data files are packaged up for the browser.

Run grunt build:[target] to build the emulator, where [target] is macplus, ibmpc or atarist.

You'll find the built files at pce-js/ and grunt run will serve them up for your browser on http://localhost:8080/. That's it.